Valve construction

ABSTRACT

A valve having at least one sealing assembly comprising a metal seat ring carried by the valve body and urged toward the valve member by circumferentially disposed coil springs. The springs are disposed within an annular retainer formed of resilient material that is U-shaped in section and which seats within the body recess. The seat ring is sealed with respect to the body and carries resilient means for sealing with respect to the valve working surface of the valve member. Preferably means is provided for injecting a viscous sealant into a region adjacent the sealing means, and means isalso provided for confining the viscous sealant to this region.

United States Patent [191 Grove et al.

I 54 I VALVE CONSTRUCTION [75] Inventors: Marvin H. Grove; Michael A.Karr,

Jr., both of Houston, Tex. 77055 [73] Assignee: M & J Valve Company,Houston,

Tex.

[22] Filed: May 15, 1972 [21] Appl. No.: 253,129

[ 51 Aug. 14, 1973 2,030,458 2/1936 McKellar i37/246.22

Primary Examiner-Harold W. Weakley Attamey-Paul D. Flehr et al.

[5 7] ABSTRACT A valve having at least one sealing assembly comprising ametal seat ring carried by the valve body and urged toward the valvemember by circumferentialiy disposed coil springs. The springs aredisposed within an annular retainer formed of resilient material that isU-shaped in section and which seats within the body recess. The seatring is sealed with respect to the body and carries resilient means forsealing with respect to the valve working surface of the valve member.Preferably means is provided for injec ting a visco as sealant into aregion adjacent the sealing means, and means is also provided forconfining the viscous sealant to this region. V

l 7 Claims, 3 Drawing Figures Patented Aug. 14, 1973 3,752,178

2 SheetsSheet 1 llll FlG 1 VALVE CONSTRUCTION REFERENCE TO RELATEDAPPLICATIONS Reference is made to copending application Ser. No. 188,097showing a ball valve having certain features incorporated in the ballvalve described herein, and applications Ser. No. 17,365 filed Mar.9,1970 and Ser. No. 176,801 filed Sept. 1, 1971, and now abandonedshowing certain features of the sealing assembly described herein.

BACKGROUND OF THE INVENTION In the construction of valves of the balland gate types, particularly in the larger sizes that may range from 6to 48 inches pipe size or larger, it is customary to use sealingassemblies that are carried by the valve body and which provide sealsbetwen the body and the valve member for closed position. As shown inU.S. Pat. Nos. 3,269,695 and 3,339,886, each assembly may consist ofresilient sealing means adapted to contact the valve working surface ofthe valve member, and a plurality of circumferentially disposed coilsprings for urging the seat ring toward the valve member. In theassembly shown in U.S. Pat. No. 3,339,886, the springs are pre-assembledwith other parts of the assembly to facilitate factory assembly andreplacement. This serves to facilitate proper location of the springsbefore the assembly is positioned within the recess of the valve body.

It has also been proposed to provide means for introducing a viscoussealant into a region adjacent the sealing means to promote effectivesealing and to reduce operating forces. However, prior constructions forthis purpose may permit the sealant to be injected into the flowpassages of the valve. Also, the sealing assemblies constructed topermit injection of sealant have been relatively complicated withrespect to the means employed for establishing seals between theassembly and the body. This means may, for example, employ two spacedO-rings between the assembly and the body, with the sealant beingintroduced into the space between the two rings and from thenceconducted to the sealing surfaces.

SUMMARY OF THE INVENTION The present invention relates generally tovalves of the ball or gate types, and particularly to valves which maybe made in the larger pipe sizes and which are provided with sealingmeans of non-metallic resilient material.

An object of the invention is to provide such valves with one or moresealing assemblies which are of simple construction and which have anarrangement permitting pre-assembly of the compression springs beforethese springs are positioned within'the valve body recess.

Another object is to provide a valve of the above character in which themeans which permits preassembly of the compression springs also servesto close the space occupied by the springs within the valve body wherebysealant can be introduced into this space for applying the same to thesealing surfaces of the valve.

Another object of the invention is to provide a valve having means forintroducing a viscous sealant and which confines the sealant to a regionadjacent the re- LII silient sealing means which contacts the valveworking surfaces of the valve member.

In general, the present invention makes use of a sealing assemblyadapted to be accommodated within a recess formed in the valve body, andhaving its one end provided with resilient means for establishingsealing contact with the valve working surface of the valve member. Thecoil compression springs provided for urging the seat ring toward thevalve member are accommodated within an annular retaining member formedof non-metallic resilient material, and which is U-shaped incross-sectional configuration. This member also serves to close thespace occupied by the compression springs whereby a viscous sealant canbe introduced into this space-and conducted to a region adjacent theresilient sealing means. Also the assembly preferably includes meanslikewise made of resilient material which is carried by the seat ringand which extends concentric to the resilient sealing means and radiallyspaced from the same to confine the region into which the sealant isintroduced.

BRIEF DESCRIPTION OF THE DRAWING Referring to the attached drawings:

FIG. 1 is a side elevational view partly in section illustrating a valveof the ball type incorporating the present invention.

FIG. 2 is an enlarged detail in section illustrating one of the sealingassemblies incorporated in FIG. 1.

FIG. 3 is a view like FIG. 2 but showing another embodiment of thesealing means suitable for use with valves of the gate type.

DESCRIPTION OF THE PREFERRED EMBOIDMENTS The ball valve illustrated inFIG. 1 consists of a body 10 which may be fabricated by welding and isprovided with aligned flow passages 11. The body hubs 12 may be arrangedfor welding to piping, or may be provided with conventional pipecoupling flanges. A valve ball 13 is disposed within the body space 14and is provided with a port 15 adapted to register with flow passages 11for open position of the valve. The body is rotatably carried bytrunnion means to enable rotation through between full open and closedpositions.

The trunnion means for the upper end of the ball consists of thetrunnion member 16 which has a flange 17 that is seated upon the upperwall portion 18 of the valve body. Its inner end portion extends withinthe bore 19 formed in the ball. It is sealed with respect to the body asby the resilient sealing means 20. Suitable bearing members 21 and 22are interposed between the trunnion member 16 and the adjacent surfacesof the bore, and these may be made of a suitable non-metallic materiallike Teflon.

An operating shaft 23 extends through the trunnion member 16 and has itsinner end coupled to the ball. Thus pins 24 are fitted into alignedopenings formed in the ball and in the lower end of the shaft, therebycoupling the shaft to the ball. Axially spaced sealing means 26 and 27serve to establish seals between the shaft and the trunnion member 16.Each of these seals may be of the resilient O-ring type. A duct 28 isshown communicating with the space between the sealing means 26 and 27for the introduction of a viscous sealant or lubricant. This duct may bein communication with a suitable sealant injecting fitting.

A plate 31 is shown overlying the upper end of the trunnion and isbetween the trunnion and the mounting plate 32. Screws 33 serve to clampthe trunnion flange 17 against the body, and screws 34 may extendthrough the mounting plate 32, plate 31 and flange 17 and threaded intothe body for clamping all of these parts together. The mounting platefacilitates the mounting of various types of operating devices upon thevalve body.

The other trunnion means consists of the trunnion member 41 whichextends through the body wall portion 42 and which has an exteriorflange 43 which is clamped by screws 44. Suitable sealing means (e.g., aresilient O-ring) 45 prevents leakage between the trunnion member 41 andthe body. The inner end of the trunnion member is accommodated withinthe bore 46 formed in the valve ball, and bearing means 47, such as asleeve formed of Teflon, serves to provide proper journalling. Anadjustable thrust plug 48 has threaded engagement with the trunnionmember 41 and is capable of adjustment from the exterior of the valvefor the purpose of adjusting the position of the valve ball with respectto the flow passages 11. The trunnion member 41 is also shown providedwith a duct 49 which is normally closed by plug 51, and which makespossible draining material from the valve body.

Annular sealing assemblies 53 are shown carried by the body and serve toestablish seals between the body and the valve ball. Although two ofthese assemblies are illustrated, in some instances one assembly willsuffice. The preferred construction for each assembly is shown in FIG.2. It consists of a seat ring 56 which is relatively rigid and which canbe made of suitable metal. One end portion 56a of this ring isaccommodated in a recess 57 formed in the valve body. The recess insection is defined by the flat shoulder surface 58 and the cylindricalperipheral surface 59. A seal is established between portion 56a of theseat ring and the peripheral surface 59 by sealing means 61, whichpreferably is of the resilient O-ring type. The portion56a of the seatring is machined to provide the thrust shoulder 62 and the annular space63. Within the space 63 there is an annular member 64 and also the coilcompression springs 65.

The member 64 is made of suitable non-metallic resilient material, suchas extrudable nylon, and it is generally U-shaped in section asillustrated. it is so dimensioned that the coil springs 65 have a snugfit within the same. Also it is so dimensioned that its base wall 64a isin contact with the shoulder surface 57 of the body recess, its outerwall portion 64b in contact with the peripheral cylindrical surface 59of the recess, and its inner portion 64c in contact with the cylindricalsurface 66 provided on the seat ring portion 56a. Preferably the wallportion 64b is somewhat shorter than portion Me.

In practice the springs are assembled together with the member 64 beforeany parts of the assembly are inserted into the valve. As previouslymentioned, the dimensioning of the member 64 is such that when the coilsprings are inserted there is a snug fit whereby the springs arefrictionally retained in proper circumferential positioning. Thereafterthis subassembly can be positioned in the surface 57 of the body recessand in contact with the outer wall portion 64b preparatory to insertingthe seat ring into the body recess.

The other end portion of the seat ring which is adjacent the valve ballis provided with resilient sealing means which is urged by the thrust ofthe springs against the valve working surface of the ball. in FIG. 2 theresilient sealing means illustrated is of the type disclosed in theabove mentioned application Ser. No. 17,365. It consists of a ring 71made of relatively hard resilient material like nylon having a durometerhardness on the A scale ranging from 60 to 85, together with anotherannular member 72 made of softer resilient material, such as a suitablesynthetic rubber or elastomer having a durometer hardness on the D scaleranging from to 90. Both members 71 and 72 are disposed and lockedwithin a recess 73 in the seat ring and are held in radial compression.An annular lip 74 is shown integral with the seat ring 56, and at thetime the members 71 and 72 are assembled within the recess '73, the lip74 can be bent by a suitable machine operation to cause the members 71and 72 to be place under radial compression and to effectively lockthese members within the recess 73. Thereafter both the members 71 and72 are machined to engage the annular valve working surfaces of theball. The exterior edge 72a of the resilient member 72 serves to engageand contact the valve surfaces of the ball to establish a seal which iseffective for relatively low pressure differentials.

With the sealing assembly described above, it is desirable to providemeans for introducing a viscous sealant into the annular region 76adjacent the resilient sealing means. For this purpose, a duct 77 isshown in the valve body and is in communication with the space 63occupied by the compression spring 65. The seat ring is shown providedwith one or more ducts 79 which serve to convey sealant into the region76. The dimensioning of wall portion 64b facilitates location anddrilling of the duct 77.

Means is provided for confining the sealant to the region 76, thuspreventing it from being injected into the flow passages of the valve.For this purpose there is shown a ribbon-like member 81 made of suitableresilient material like nylon, and which is inserted and retained withina recess or slot 82 formed in the seat ring. One edge of this ribbonterminates in close relationship or in contact with the valve ball. Asuitable fitting 83 is carried by the body whereby sealant underpressure can be introduced through this fitting and through duct 77 intothe space 63 and from thence through ducts 79 into the region 76.

The sealing assembly described above has a number of desirable features.The construction is relatively inexpensive to manufacture, and assemblyof the parts is greatly simplified. The annular member 64 which is U-shaped in section not only serves to retain the coil springs during andafter assembly, but in addition provides sufi'icient sealing means toretain lubricant introduced into the space.63 under pressure, thuscausing such sealant to be introduced into the region 76. The sealantwhen introduced into the region 76, which is immediately adjacent theinner periphery of the resilient sealing means, is prevented from beinginjected into the flow passages of the valve by the retaining ribbon 81.

FIG. 3 illustrates parts of a gate valve with another embodiment of thesealing assembly. In this instance the seat ring 86 has one end portionadapted to cooperate with the surface 87 of the valve gate 88.

The general character of the gate valve may be as shown in US. Pat. No.3,481,580. The valve body 89 is machined to provide the recess 91 whichis defined by the shoulder surface 92 and the cylindrical peripheralsurface 93. Sealing means 94 of the resilient O-ring type serves toestablish a seal between the seat ring 86 and the peripheral surface 93of the body. The member 64 is the same as in FIG. 2 and serves toaccommodate the coil compression springs 96. The seat ring also carriesthe annular member 97 corresponding to the member 71 of FIG. 2, and themore resilient member 98 corresponding to the member 72 of FIG. 2. Thesemembers are finished to engage the valve working surface 87 of the gate.The seat ring is also provided with a ribbon-like member 99 ofnon-metallic material like nylon, corresponding to the member 81 of FIG.2, and serving to retain sealant in the region 101. One or more ducts102 are provided in the seat ring and serve to connect the spaceoccupied by the springs 96 with the region 101. The body is providedwith an exterior fitting 103 for the introduction of viscous sealantunder pressure, and this connects with the space occupied by the springs96 through duct 104.

The assembly shown in FIG. 3 functions in substantially the same manneras described in connection with FIG. 2. The compression springs arepre-assembled in the U-shaped member 64, and the fit between the springsand the inner and outer side walls of member 64 is sufficient to retainthe springs in the positions desired. This assembly is then fitted uponthe seat ring 86, after which the seat ring is inserted into the recess91 of the body. While the member 64 is not intended to form afluid-tight seal, it does form a sufficient seal to retain viscoussealant introduced through the fitting 103 whereby such sealant can beintroduced under pressure through duct 102 into the region 101.

In connection with both assemblies, FIGS. 2 and 3, it is assumed that aseal is to be maintained upon the upstream side of the valve. Thus inFIG. 2 the diameter of the recess surface 59 which is engaged by thesealing members 61 is somewhat greater than the diameter of the face 72aof member 72, which establishes a seal with respect to the ball. Thusassuming that there is a pressure differential between the upstream flowpassage and the body space, the line pressure urges the seat ring towardthe valve ball. Substantially the same proportioning is shown in FIG. 3.In the event pressure differential is applied in the reverse direction,or in other words, in the event the pressure in the valve body exceedsthe pressure in the upstream flow passage, such pressure isautomatically relieved past the sealing means, either by slightretraction of the seat ring away from the valve ball, or by escape ofsuch pressure past the face 72a of the member 72.

With respect to the ball valve shown in FIG. I, the valve ball iscarried by the trunnions in such a manner that it carries the thrust ofline pressure when in closed position. Thus the thrust of line pressureis not carried by the sealing assembly upon the downstream side of tionsto control flow through the passages, a sealing assembly surrounding oneof the flow passages and carried by the body, said assembly including aseat ring, the body having a recess serving to accommodate one portionof the seat ring, the recess in section being defined by an end shoulderand a peripheral surface that is cylindrical, sealing means of resilientnon-metallic material carried by the other end portion of the seat ring,the valve member having an annular valve surface formed thereon whichsurrounds said one passage for closed position of the valve member andwhich is disposed to engage said sealing means, means forming a sealbetween said first-named seat ring portion and the body, a plurality ofcircumferentially disposed compression springs disposed within the bodyrecess and engaging said seat ring to urge the same toward the valvemember, and spring accommodating means comprising an annular member madeof resilient nonmetallic material, said member being U-shaped in sectionand dimensioned to seat against the shoulder of the recess, said springsbeing accommodated within said member.

2. A valve as in claim 1 in which said annular member made ofnon-metallic resilient material has its outer peripheral wall portion oncontact with the peripheral surface of the recess and its inner wallportion in contact with the seat ring.

3. A valve construction as in claim 2 in which the outer wall portion isshorter than the inner wall portion to facilitate introduction ofsealant.

4. A valve as in claim 2 together with means for introducing a viscoussealant into the recess space occupied by the springs. I

5. A valve construction as in claim 4 in which the seat ring is providedwith a duct serving to conduct viscous sealant from the space occupiedby the springs to a region near the resilient sealing means engaging thevalve the valve. With a gate valve of the type referred to member.

6. A valve construction as in claim 5 together with sealant retainingmeans carried by the seat ring and serving to enclose the said regioninto which sealant is introduced, said last means comprising a member ofresilient material disposed concentric to and spaced radially from thesealing means.

7. In a valve construction, a valve body having aligned flow passages, avalve member disposed within the body and movable between open andclosed positions to control flow of fluid through the passages, at leastone sealing assembly surrounding one of the flow passages and carried bythe body, said assembly including a relatively rigid seat ring, the bodyhaving a recess serving to accommodate one portion of the seat ring,

means forming a fluid-tight seal between one end portion of said seatring and the body, sealing means of resilient non-metallic materialcarried by the other end portion of the ring, said valve member havingan annular surface formed thereon which surrounds said one passage forclosed position of the valve and which is disposed to engage saidresilient sealing means, means for introducing a viscous sealant intothe region adjacent said sealing means, and sealant retaining meanscarried by the seat ring and serving to enclose said region, said lastmeans comprising a ribbon-like member of resilient non-metallic materialmounted upon the seat ring and disposed concentric to and spacedradially from the sealing means.

1. In a valve construction, a valve body having aligned flow passages, avalve member disposed within the body and movable between open andclosed positions to control flow through the passages, a sealingassembly surrounding one of the flow passages and carried by the body,said assembly including a seat ring, the body having a recess serving toaccommodate one portion of the seat ring, the recess in section beingdefined by an end shoulder and a peripheral surface that is cylindrical,sealing means of resilient non-metallic material carried by the otherend portion of the seat ring, the valve member having an annular valvesurface formed thereon which surrounds said one passage for closedposition of the valve member and which is disposed to engage saidsealing means, means forming a seal between said first-named seat ringportion and the body, a plurality of circumferentially disposedcompression springs disposed within the body recess and engaging saidseat ring to urge the same toward the valve member, and springaccommodating means comprising an annular member made of resilientnon-metallic material, said member being U-shaped in section anddimensioned to seat against the shoulder of the recess, said springsbeing accommodated within said member.
 2. A valve as in claim 1 in whichsaid annular member made of non-metallic resilient material has itsouter peripheral wall portion on contact with the peripheral surface ofthe recess and its inner wall portion in contact with the seat ring. 3.A valve construction as in claim 2 in which the outer wall portion isshorter than the inner wall portion to facilitate introduction ofsealant.
 4. A valve as in claim 2 together with means for introducing aviscous sealant into the recess space occupied by the springs.
 5. Avalve construction as in claim 4 in which the seat ring is provided witha duct serving to conduct viscous sealant from the space occupied by thesprings to a region near the resilient sealing means engaging the valvemember.
 6. A valve construction as in claim 5 together with sealantretaining means carried by the seat ring and serving to enclose the saidregion into which sealant is introduced, said last means comprising amember of resilient material disposed concentric to and spaced radiallyfrom the sealing means.
 7. In a valve construction, a valve body havingaligned flow passages, a valve member disposed within the body andmovable between open and closed positions to control flow of fluidthrough the passages, at least one sealing assembly surrounding one ofthe flow passages and carried by the body, said assembly including arelatively rigid seat ring, the body having a recess serving toaccommodate one portion of the seat ring, means forming a fluid-tightseal between one end portion of said seat ring and the body, sealingmeans of resilient non-metallic material carried by the other endportion of the ring, said valve member having an annular surface formedthereon which surrounds said one passage for closed position of thevalve and which is disposed to engage said resilient sealing means,means for introducing a viscous sealant into the region adjacent saidsealing means, and sealant retaining means carried by the seat ring andserving to enclose said region, said last means comprising a ribbon-likemember of resilient non-metallic material mounted upon the seat ring anddisposed concentric to and spaced radially from the sealing means.